whoaitstony

iTrader: (1)

Just bought a 04 acura tl 6 speed with about 100k miles. a couple days after driving the car i get the a flashing CEL. after that the CEL light stays on and i check the codes and get P0301, P0302, P0304, P0306 (for cylinder misfire 1,2,4, and 6), and P0300 for random/multiple cylinder misfire detected. Once that happened i changed out the spark plugs, and a couple days later the CEL comes on again. I also ended up swapping out the EGR and timing belt and same CEL's pop up days later. Last thing i can think of is getting my valves adjusted and i'm taking it to my buddie's shop once i get the chance. Any members here with the same or similar problem as mine have any idea what might cause this? Car also came with K&N cold air intake and comptech exhaust, i dont know if that might be causing my problem. Any help would be appreciated, thanks.

csmeance

did you use NGK plugs? Some plugs like the Bosch ones can cause issues like these in the TL.

Also are you using premium fuel? Try running a bottle of fuel cleaner through the system. Also check the coil-packs.

I hate cars

I read ahead and saw random misfires and then went back and sure enough it was a 6 speed.

There was a TSB on some years for false misfire codes, you might want to see if yours is listed.

Have you ever overreved it? I'm not talking about hitting the rev-limiter, I'm talking about downshifting and hitting the wrong gear by accident.

You can try the usual fuel system cleaners, plugs, etc. But unless you got a bad batch of gas or it's the TSB software issue, with all of those random misfires it points to an overrev and bent valves.

whoaitstony

iTrader: (1)

yeah i used NGK plugs when i got them changed and always pumped premium fuel from mobil or chevron. i think i might have to check out that TSB and see if that might be the problem. also i havent over revved the car or misshifted since ive owned it this past month, and i also have used seafoam a week or two ago but no luck. was at the shop today to recheck my coilpacks and coilpack 6 had a little oil on the coilpack. wasnt alot but just around the tip of the coilpack so i cleaned it off, would this be a problem?

I hate cars

If it had a single cylinder misfire I would say that could be it. But with multiples it's something that can effect the whole engine like a bad batch of fuel, not all injectors getting plugged at once. Bent valves, not all spark plugs fouling at the same time, etc.

whoaitstony

iTrader: (1)

yeah i'm most likely gonna go get the valves adjusted when i get the chance so i can see if the valves are bent or not. if they're not bent i'm guessing bad injector's. btw are you talking about this TSB? http://techinfo.honda.com/Rjanisis/pubs/SB/B03-033.PDF . if i wanted to check this out i'd just go to a honda/acura dealer and see if they'd check it out and update it for me? thanks for all the info

mr.ef8

My tl is going something similar. It shakes on cold starts like it was misfiring then it gots warm and its not as bad you can see it on the motor it shakes little every 3-4 seconds on idle. Any suggestions guys?

CamboSoup562

This is normal, from what ive heard if this is happening when you first start the car for the day, the car misfires on purpose when the engine is cold so it can heat up faster. Scared me a bit at first too...i would get used to letting the engine heat up in the morning or whenever you first start your car. Plus, when the engine is heated up, you save more gas

robocam

Will a compression test tell you if your valves are messed up due to overrevving? If so, is there a specific type of compression test I should ask for?

And how does overrevving damage the valves?

If that is what needs to be repaired, what all is involved? I would like to know so that I can get price quotes. Should I not get a valve adjustment (at the 105k service) because one would probably be included in this job?

Also, what would happen if I didn't have this repaired?

thanks!

Pete Kotce

Had a similar problem with my 04 tl (190,000)
with help from this site was able to narrow it down. So i decided to log in make a post.

had a week of -15 degree weather followed by a week of 50 degree weather water in lines lead to multipull missfire p0300 301 thru 306 with a 2197 for ecm lean. Did the plugs which did not look to be in bad shape at all. Air filter to make sure it hadnt become waterlogged. Cleabed the tb . Gas an seafoam treatment. Still didn't completely run right. Pulled each individual coil pack while running and found #3 was not good. Even though scanner pulled up all 6. Replaced the one she came right back to strength. Swapped the rest the next week.

thanks for your help. Trying to do my part topay it forward.

Finalichigo

So I'm currently having this issue I'll leave a link to all the work done before the misses the car would shut off when I stopped


Still trying to figure out why

El_Cheapo

So what's your issue? The video says the car is running fine.

Finalichigo

a few days later all cylinders started missing again and it will stop for a few min sometimes then go back to missing again

El_Cheapo

Very odd that all cylinders are misfiring. Hondas shows multiple cylinder misfires when in reality it's only one. Make sure it's either all or one first. Try doing a cylinder power balance test.

What codes?

Finalichigo

300 to 306 random multiple then each cylinder

El_Cheapo

Watch this video. Maybe you can try some of the same tests.